Navigate normally from camera perspective?
If you wish, you can lock the Camera to the perspective view. That means that whenever you navigate in the 3D viewport the camera will 'follow' you in the view, copying the location and rotation of your navigation. In effect, in this mode it will look like you have never left the camera perspective as the dark border around the camera and the camera border itself, will remain visible.

It can be enabled in the properties panel (N) under the 'View' section:



At any point you can then disable the option and the camera will remain at the position you navigated to meaning you can use this to move you camera into position and then leave it at the desired location.